Technical Field
The present invention relates to a volatile oil for cosmetics having excellent volatility, hair care properties, and skin care properties, and relates to a volatile, oil that may be used for, for example, hair cosmetics and external preparations for skin.
Background Art
As hydrocarbons that have been conventionally used as volatile oils, hydrocarbons having a carbon number of 6 to 12 are known, including, for example, n-hexane, isohexane, cyclohexane, n-octane, isooctane, n-nonane, n-decane, and isododecane. Unfortunately, there is a problem in that those volatile oils lack safety since their flash point is low at 50° C. or below. When these volatile oils are used for oils contained in cosmetics or cleansers for hair and skin, there are problems in that they are too stimulative to skin including scalp and mucous membrane, and they are so volatile that moisture is likely to evaporate from the surface layer of a living body.
Also, in case of hydrocarbons having a carbon number of 15 or more including, for example, n-pentadecane and isohexadecane, improvements in performance such as higher flash points and less stimulation to skin and mucous membranes are expected since they have higher molecular weights. However, they have a problem that, as their volatility is lower, oil is likely to linger, leaving poor texture when applied to hair or skin.
Based on this background, Patent Literature 1, for example, discloses a non-silicone composition in which a hydrocarbon having a carbon number of 12 to 14, a hydrocarbon having a carbon number of 13 to 16, and a non-volatile hydrocarbon are combined, as a volatile oil having excellent volatility, high flash point as well as safety oil a human body. Moreover, in the field of cosmetics, Patent Literature 2, for example, discloses hair cosmetics in which cyclic silicones such as cyclomethicone are used as a volatile component (see claim 1, for example, in the same Literature). Also, Patent Literature 3 discloses external preparations for skin in which cyclic silicones such as cyclomethicone are used as a volatile component (see paragraphs [0039] and [0040] in the same Literature).